The invention relates to a laminar flow water jet for a hydrotherapy bath or spa system and a hydrotherapy bath system with two or more jets providing a converging flow pattern.
It is widely know in the art how to inject water and/or air through orifices, jets or nozzles in just about any given direction. It is known to direct water towards an occupant(s), or a certain body portion of an occupant, in a whirlpool bath. It is known that the occupant's body may alter or block the flow from a jet or possibly cooperate with the jet to produce a desired flow pattern as disclosed for example in U.S. Pat. No. 4,953,240 and U.S. Pat. No. 4,383,340). U.S. Pat. No. 4,383,340 discloses the use of multiple jets to produce more powerful flows. U.S. Pat. No. 5,548,854 discloses sequentially pulsating flows. Thus, it is known to impact multiple body parts simultaneously or sequentially. It is known to direct water parallel to a surface of the tub or a surface of an occupant to extend the area of impact of a jet. Representative of the art is U.S. Pat. No. 6,760,932, U.S. Pat. No. 6,643,859, and U.S. Pat. No. 6,182,303. Turbulent flow is generally presumed, intended, or desired for a massaging effect on the human body. Entrained air is commonly used to increase turbulence.
Laminar flow may be more desirable than turbulence in certain limited situations. For example, a uniform laminar current may be desirable to swim against in a swim training tub or pool as disclosed in U.S. Pat. No. 5,662,558 and U.S. Pat. No. 5,207,729, or to produce Karman vortices for vibratory weight reduction as disclosed in U.S. Pat. No. 5,010,605. Laminar water jets have been used for desirable visual effects in fountain displays as disclosed in U.S. Pat. Publication No. 2005/0235407A1, and/or for waterfall displays for tubs or ponds or pools as disclosed in U.S. Pat. Publication No. 2005/0155144A1. In producing or using laminar flow, various vanes, holes, dividers, and restrictions in various parts of the flow channels and/or the jets have been provided as disclosed for example in U.S. Pat. No. 2005/0155144A1. Also provided are anti-cavitation plates, stabilizing plates or fins and the like as disclosed for example in U.S. Pat. No. 5,662,558 and U.S. Pat. No. 5,207,729.
What is not known or taught in the art is a whirlpool-type, hydrotherapy bath having a combination of laminar jets that produce a soothing, therapeutic laminar flow. What is needed is a laminar flow jet having a streamlined internal shape or design. What is needed is at least two laminar jets directing water streams substantially parallel to a tub wall into a convergent flow zone. What is needed is a tub with laminar jets that produce a flow pattern simulative of a natural river current flow over an occupant's body. What is needed is a parallel flow jet that is rotatable for selection of flow direction. What is needed is tub with structural features that cooperate with laminar jets in the presence of a human body to produce therapeutic flows that are not blocked by the body and that exhibit delayed, controlled turbulence. The present invention meets one or more of these needs.
After much experimentation and the application of computational fluid dynamics, we have discovered how to design a laminar jet and how to introduce and maintain a laminar flow over or around specified features for a relatively long distance in a hydrotherapy bath. Desirable flow effects result when one or more convergence zones are created using surface features within the tub and directing two or more rotatable jet bodies in such a way that the water flow paths converge.